Inhibit DSE for implicit loads via calls.
Document support for Lua 5.2 extension of loadfile().
Fix compiler warning.
Tighten requirements for non-default optimization flags.

FOLD is required for FWD/DSE optimizations.
Fix builtin string to number conversion for overflow digits.
FFI: Fix tailcall in lowest frame to C function with bool result.
Fix optional argument handling while recording builtins.
Fix optional argument handling in table.concat().
FFI: Ignore CTF_LONG in ffi.istype().
Add partial support for building with MingW64 GCC 4.8-SEH.

Error handling works, C++ interoperability generally works.
C++ destructors in libs compiled with G++ cause trouble (ok with MSVC).
FFI: Fix calling conventions for 32 bit OSX and iOS simulator.

OSX uses -freg-struct-return, which returns small structs in regs.
Thanks to Adriano Bertucci.
FFI: Fix calling conventions for ARM hard-float EABI.

Properly classify nested (non-transparent) structs.
Merge branch 'master' of luajit-2.0
Improve and complete GDT documentation chapter